Work at the Dr. Francomano laboratory continues to focus on the human hereditary disorders of connective tissue including the Marfan Syndrome and a number of skeletal dysplasias. Dr. Iain McIntosh is concentrating on the positional cloning of the nail patella gene on human chromosome 9q34 and the studies of type 10 collagen mutations in the Schmid type metaphyseal dysplasia. Analysis of fibrillin mutations in the Marfan syndrome and related disorders are being spear-headed by Dr. Maureen Johnson in collaboration with Dr. Harry Dietz at Johns Hopkins. A major focus of the laboratory continues to be the analysis of FGFR3 mutations in achondroplasia and hypochondroplasia, two of the more common human skeletal dysplasias. These studies are being done under the guidance of Dr. Gary Bellus. Finally, linkage studies are underway on several additional skeletal dysplasias. The chromosomal localization of the Ellis-van Crevald syndrome, pkynodysostosis and type II polysyndactyly have been found over the past year in collaboration with Dr. Mihael Polymeropoulos of the Laboratory of Genetic Disease Research.